High-Mass MALDI-MS Using Ion Conversion Dynode Detectors: Influence of the Conversion Voltage on Sensitivity and Spectral Quality

Research Article

Abstract

With the development of special ion conversion dynode (ICD) detectors for high-mass matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS), the mass-to-charge ratio is no longer a limiting factor. Although these detectors have been successfully used in the past, there is lack of understanding of the basic processes in the detector. We present a systematic study to investigate the performance of such an ICD detector and separate the contributions of the MALDI process from the ones of the ion-to-secondary ion and the secondary ion-to-electron conversions. The performance was evaluated as a function of the voltages applied to the conversion dynodes and the sample amount utilized, and we found that the detector reflects the MALDI process correctly: limitations such as sensitivity or deviations from the expected signal intensity ratios originate from the MALDI process itself and not from the detector.

Graphical abstract

Keywords

MALDI-ToF-MS High-mass protein analysis Ion conversion dynode Sensitivity Resolution 

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Copyright information

© American Society for Mass Spectrometry 2014

Authors and Affiliations

  1. 1.Department of Chemistry and Applied BiosciencesETH ZürichZürichSwitzerland

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